I however feel the greater testimony of Scripture is that it was known from the beginning.
Now where it's used in the narrative voice of Genesis one could easily say that's just Moses giving the text it's final form. But Abraham in Genesis 22 names a location Yahuahjirah, it's not just an editorial note, it says Abraham gave it that name.
The end of Genesis 4 says in the days of Enosh men began to call upon the name of Yahuah. While this is irrelevant to it's relevance to this issue, I want to state my disagreement that "call upon" should be translated Profane here which I see asserted often. This is the exact same terminology used when Genesis latter tells us Abraham "called upon" the name of Yahuah, in Genesis 12:8 and Isaac in 26:25.
There is no hint in Exodus that Yahweh was a new name revealed first to Moses. On the contrary, the success of his mission depended on the use of the familiar name for validation by the Israelites—The Sentence in Biblical Hebrew (1974:102).And
[The] texts of Genesis show that Yahweh had appeared to the patriarchs (Gen 12:1, 17:1, 18:1, 26:2, 26:24, 26:12, 35:1, 48:3), and that he spoke to each one of them (Gen 12:7, 15:1, 26:2, 28:13, 31:3). The name “Yahweh” occurs 162 times in Genesis, 34 of those times on the lips of speakers in Genesis (W. C. Kaiser, Jr., “Exodus,” EBC 2:340-41). They also made proclamation of Yahweh by name (4:26, 12:8), and they named places with the name (22:14). These passages should not be ignored or passed off as later interpretation.Exodus 6:3 has been addressed on this issue in a few ways. One is that "name" here is being used in the sense of character. Many are discussed here from a Karaite Jewish perspective, some things he mentioned being not fulfilled yet we believe are. Another is that that the "not" part is meant to be Rhetorical. Taken form this page quoting a user named Frank Luke.
As for Exodus 3. What happens there can be taken many ways too. In fact the implication can absolutely be read as implying it's a name already known. The scene is also believed to reflect Moses entering this on an erroneous Pagan notion that knowing a god's name gives you power over him, he grew up a Prince of Egypt remember.
As for the desire to allege the name is Pagan. Attempts to find it in Canaanite or Arabic texts or inscriptions that clearly predate Moses or even Solomon are all lacking. Especially since I believe in Revised Chronology.
The best argument for a Pagan origin for Yah is the Egyptian moon god Iah. How to pronounce Egyptian names has been lost, Iah is the default you see on Wikipedia, but it also states other alternatives like Yah, Jah, Joh or Aah. They become less similar to the Hebrew Yah as we go down the list. Other equally likely possibilities cod include Ieh, Yeh, or Jeh, which will prove ironic later. That the Iah theophoric name Ahmose is rendered in Greek texts like Hedotus and Manetho as Amasis or something similar, I consider support for something like Aah being correct pronunciation.
Aah could be etymologically related to Ajah/Aiah, which is not a Yah theophoric name but can easily be confused for one, it comes from the Hebrew word for Hawk or Kite or Vulture. The Egyptian moon god Khonsu's name is spelled with Hieroglyphics that resemble similar kinds of birds.
Iah isn't even the main Egyptian Moon god. There were two for the Moon just as there were for the Sun (all four were male unlike in many other cultures). The main Sun deity was Ra, while Aten/Atum was a lesser one, more like the name for the visible Solar disc itself. For the moon Iah was equivalent to Aten not Ra, the main Moon deity was Khonsu. Still Akhnetan choose Aten over Ra for his Henotheistic Sun cult, so hypothetically someone could have done the same with Iah for a Moon cult.
I'm curious what the oldest Egyptian references to Iah are. I'm wondering if it could have come from in some way the influence of Joseph and later got corrupted.
Fringe theorists will suggest that the Hebrew name for the Moon, Yerech/Yerikh often transliterated into English as Jerah/Jereh, was originally identical to Yahweh but that the scribes changed the spelling of one or the other to obscure it. But Yerach is the same spelling non monotheistic Semites used in the texts we have for them.
The words only have in common beginning with the same letter, as do many other not related Hebrew words. The two letters for "h" are different, Yah uses Heh and Yerach uses Heth/Cheth.
Another things people might use to support a Yahweh as a Moon God theory is the fact that the Torah uses a Lunar calendar. Mostly I think God wanted that to be contrary to the Solar Calendar as the standard of their Canaanite neighbors. But many other Calendars have been Lunar including the Attic Greeks without it meaning they favored Moon worship over other gods.
Also I've seen the theory out there that the name of Sinai comes from Sin the Akkadian Moon god, and Horeb means shining (a meaning linked to lunar deities like Phoebe). I consider neither of those the most likely etymology. Horeb is spelled identically to the Hebrew word for Sword, and is also related to Cherub, Cherub's similarity to Sword is part of the wordplay of Genesis 3:24. The name Sinai first occurs in Exodus 16:1, which also refers to a place called Sin, the Hebrew spelling implies they come from the same root as the Sinite tribe of the Canaanites. It was probably populated by Sinites first then the Midianites and/or Kenites drove them out. Now it may be the Akadian deity's name comes from the Sinites, who knows.
To show I'm not a hypocrite I want to say I no longer agree with labeling Allah a moon god. The main Idol of the Pre-Islamic Kaaba was Hubal, who was not a Moon god but the Nabatean form of Baal. There are many theories as to the origin of the Crescent Moon being a Muslim Symbol, nothing in the Koran actually calls for it to my knowledge. The theory I favor is it being connected to them using a Lunar calendar. Some Pre-Islamic Arabian Jews are known to have used a similar symbol for that reason. The Muslims might have copied them.
The argument for the name being a foreign insertion into the Hebrew texts has two basis really, but a third implication from that is that all Yah theophoric names as well as the expression halleluyah should replace the Yah part with Ye or Yeh.
The first basis is a supposed inconsistency between YHWH and the I AM statement that we assume was when the name was revealed.
The Hebrew says "Ehyeh asher Ehyeh" which gets translated "I AM that I AM". The Hebrew word for I AM is Hayah, but Ehyeh is the first person form. Someone saying it to refer to someone else would say Hayah.
An interesting fact is that Hebrew and many ancient languages unlike English will use their definite article before a personal name. The Hebrew definite article is just the letter Heh added to a word as a prefix and pronounced Ha. So really every occurrence of Yah is really HaYah.
So really the I AM statement is more like a pun on an existing name, not the origin of one.
The second Basis is arguably more then one but all from how the Greek New Testament renders things. But the New Testament passage that works against them they say is corrupt. So they're selective.
Now this theory doesn't necessarily assert Ehyeh was the original everywhere you see YHWH. Based on the common assumptions about Exodus 6:3 they would probably say it should be El Shaddai everywhere it occurs in Genesis.
And they may use the Septuagint and New Testament quotations of the Hebrew Bible to support saying Adonai (Lord) was in the original. The Septuagint which I have expressed my problems with before was the product of developing Jewish superstition that you shouldn't pronounce the name, that came from a misunderstanding of the 4th Commandment. The Hebrew Bible is against that idea however, it record the name being spoken in dialogue by humans often.
New Testament quotations I think happen to also do this because for the New Covenant Yeshua/Iesous/Jesus has replaced Yahuah as the personal name of God.
And they use the Greek spelling of Jesus to support their replacing of Yah with Ye/Yeh. Problem is Eta following the Iota is a common practice of Greek transliteration that does not necessarily tell us how it was pronounced in the original language, we see it with many names that started with a Yot. Though in this case I think the Holy Spirit might have been playing with how Eta has an ambiguous relationship to the "h" sound.
Revelation 19 verifies that Hallelujah should be pronounced ending with an A sound rather then an E. So they allege that word wasn't originally in the text at all. They don't even say it's absent from any old texts, which it could very well be from the Alexandrian corpus. Their main argument is that Revelation 19:1-6 is a repeat of part of Revelation 7. There may be thematic or poetic parallels there, but they were blatantly arguing for a non Chronological view of Revelation.